Abstract：
Non-photochemical quenching (NPQ) protects plants from photodamage caused by excess light energy. Substantial variation in NPQ has been reported among different genotypes of the same species. However, comparatively little is known about how environmental perturbations, including nutrient deficits, impact natural variation in NPQ kinetics. Here, we analyzed a natural variation in NPQ kinetics of a diversity panel of 225 maize (Zea mays L.) genotypes under nitrogen replete and nitrogen deficient field conditions. Individual maize genotypes from a diversity panel exhibited a range of changes in NPQ in response to low nitrogen. Replicated genotypes exhibited consistent responses across two field experiments conducted in different years. At the seedling and pre-flowering stages, a similar portion of the genotypes (∼33%) showed decrease, no-change or increase in NPQ under low nitrogen relative to control. Genotypes with increased NPQ under low nitrogen also showed greater reductions in dry biomass and photosynthesis than genotypes with stable NPQ when exposed to low nitrogen conditions. Maize genotypes where an increase in NPQ was observed under low nitrogen also exhibited a reduction in the ratio of chlorophyll a to chlorophyll b. Our results underline that since thermal dissipation of excess excitation energy measured via NPQ helps to balance the energy absorbed with energy utilized, the NPQ changes are the reflection of broader molecular and biochemical changes which occur under the stresses such as low soil fertility. Here, we have demonstrated that variation in NPQ kinetics resulted from genetic and environmental factors, are not independent of each other. Natural genetic variation controlling plastic responses of NPQ kinetics to environmental perturbation increases the likelihood it will be possible to optimize NPQ kinetics in crop plants for different environments.
摘要：
非光化学猝灭(NPQ)保护植物免受由过量光能引起的光损伤。据报道，同一物种的不同基因型之间NPQ存在大量差异。然而,关于环境如何扰动，包括营养缺乏,影响NPQ动力学的自然变化。这里,我们分析了在氮充足和氮缺乏的田间条件下225种玉米（ZeamaysL.）基因型的多样性面板的NPQ动力学的自然变异。来自多样性小组的单个玉米基因型对低氮的反应表现出NPQ的一系列变化。在不同年份进行的两个现场实验中，复制的基因型表现出一致的反应。在幼苗和开花前阶段，基因型的相似部分(~33%)显示下降，在低氮条件下NPQ相对于对照没有变化或增加。在低氮条件下，与具有稳定NPQ的基因型相比，在低氮条件下NPQ增加的基因型在干生物量和光合作用方面也显示出更大的减少。在低氮条件下观察到NPQ增加的玉米基因型也表现出叶绿素a与叶绿素b的比率降低。我们的结果强调，由于通过NPQ测量的过量激发能量的热耗散有助于平衡吸收的能量与利用的能量，NPQ变化是在低土壤肥力等胁迫下发生的更广泛的分子和生化变化的反映。这里,我们已经证明了NPQ动力学的变化是由遗传和环境因素引起的，不是彼此独立的。控制NPQ动力学对环境扰动的塑性响应的自然遗传变异增加了在不同环境下优化作物植物中NPQ动力学的可能性。
